National Geographic : 1927 Sep
©Rise Studio NATURE A MASTER SCULPTOR South Dakota's "Bad Lands" were covered by a great sea in fairly recent geologic time. In the water, sediments ofclay and soft rocks were laid down. When the land rose above the sea, rain and winds attacked the soft deposits, and through hundreds ofthousands ofyears have carved them into terraces, spires, castles, and hundreds of other weird forms. Tree growth is absent from most of this region. Itsbare, inhospitable appearance accentuates by contrast the charms of the forest-covered, well-watered Black Hills, which it adjoins (see,also, text, page 328).